JP6478022B2 - Illumination light source and illumination device - Google Patents

Description

  The present invention relates to an illumination light source and an illumination device including the same.

  Semiconductor light-emitting elements such as light-emitting diodes (LEDs) are expected to serve as light sources for various products because of their small size and long life. Among these, a bulb-type lamp using an LED (LED bulb) has been actively developed as an illumination light source that substitutes for a conventionally known bulb-type fluorescent lamp or incandescent bulb (see, for example, Patent Document 1). .

  The LED bulb, for example, surrounds the LED module, a globe (cover) covering the LED module, a support base (module plate) on which the LED module is placed, a drive circuit for causing the LED module to emit light, and the drive circuit It has a heat sink and a base for receiving power.

JP 2011-146241 A

  In the LED bulb, there is a problem that the cost of the heat radiating member for radiating the heat generated in the LED module (light emitting module) is high. For example, in an LED bulb, a metal plate on which an LED module is placed and a cylindrical heat sink into which the metal plate is fitted are provided as a heat dissipation member.

  The present invention has been made to solve such a problem, and provides an illumination light source and an illumination device that can efficiently dissipate heat generated in a light emitting module by a low-cost heat radiating member. Objective.

  In order to achieve the above object, one aspect of a light source for illumination according to the present invention includes a light emitting module, a globe covering the light emitting module, a drive circuit for causing the light emitting module to emit light, and a heat sink surrounding the drive circuit. And a housing having an outer portion surrounding at least a part of the heat sink, wherein the heat sink is constituted by a plurality of heat transfer pieces, and each of the plurality of heat transfer pieces is formed by the light emitting module. The first heat transfer plate is fixed, and the second heat transfer plate is formed so as to be bent from the first heat transfer plate and faces the inner surface of the outer shell.

  According to the present invention, the heat generated in the light emitting module can be efficiently radiated by the low cost heat radiating member.

It is sectional drawing of the LED bulb which concerns on embodiment. It is a top view of the LED module in the LED bulb which concerns on embodiment. It is a top view of the heat sink in the LED bulb which concerns on embodiment. In the LED light bulb which concerns on embodiment, it is a figure for demonstrating a mode when incorporating a heat sink in a housing | casing. It is sectional drawing of the illuminating device which concerns on embodiment. It is sectional drawing of the LED bulb which concerns on the modification 1. It is a fragmentary sectional view of the LED bulb concerning the modification 2. It is a top view which shows the modification of a heat sink. It is a top view which shows the modification of an LED module.

(Embodiment)
Embodiments of the present invention will be described below. Note that each of the embodiments described below shows a preferred specific example of the present invention. Therefore, numerical values, shapes, materials, components, arrangement positions and connection forms of components, and steps and order of steps shown in the following embodiments are merely examples and are not intended to limit the present invention. Absent. Therefore, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims showing the highest concept of the present invention are described as optional constituent elements.

  Each figure is a mimetic diagram and is not necessarily illustrated strictly. In each figure, substantially the same configuration is denoted by the same reference numeral, and redundant description is omitted or simplified.

[LED bulb]
In the following embodiments, a light bulb shaped LED lamp (LED light bulb) serving as a substitute for a light bulb shaped fluorescent lamp or an incandescent light bulb will be described as an example of an illumination light source.

  FIG. 1 is a cross-sectional view of an LED bulb 1 according to an embodiment. In FIG. 1, the alternate long and short dash line drawn along the vertical direction of the drawing indicates the central axis J of the LED bulb 1. In the present embodiment, the central axis J is the optical axis (lamp axis) of the LED bulb 1 and coincides with the axis of the globe 20 (globe axis). The central axis J is an axis that becomes a rotation center when the LED bulb 1 is attached to a socket of a lighting fixture (not shown), and coincides with the rotation axis of the base 60.

  As shown in FIG. 1, the LED bulb 1 includes an LED module 10, a globe 20 that covers the LED module 10, a drive circuit 30 that causes the LED module 10 to emit light, and a heat sink that is configured to surround the drive circuit 30. 40 and a housing 50 surrounding at least a part of the heat sink 40. The LED bulb 1 further includes a base 60, lead wires 71 to 74, and a screw 80.

  In the present embodiment, the LED bulb 1 is configured as an envelope by the globe 20, the housing 50, and the base 60.

  Hereinafter, the details of each component of the LED bulb 1 will be described with reference to FIG.

[LED module]
The LED module 10 is a light emitting device (light emitting module) that emits light of a predetermined color (wavelength). The LED module 10 is configured to emit white light, for example.

  The LED module 10 is disposed inside the globe 20. The LED module 10 is fixed to the heat sink 40 and emits light by power supplied from the drive circuit 30.

  FIG. 2 is a top view of the LED module in the LED bulb 1 according to the embodiment.

  As shown in FIGS. 1 and 2, the LED module 10 includes a substrate 11 and a light emitting element 12 disposed on the substrate 11.

  The substrate 11 is a mounting substrate for mounting the light emitting element 12. The substrate 11 is, for example, a substantially circular plate-like substrate in plan view, and is fixed to the heat sink 40. Specifically, the substrate 11 is placed on the first heat transfer plate 41 of each of the four heat transfer pieces 40 a to 40 d constituting the heat sink 40. The substrate 11 is provided with a through-hole 11 a for inserting a screw 80, and the substrate 11 and the first heat transfer plate 41 are screwed together with a screw 80. The method for fixing the substrate 11 and the heat sink 40 is not limited to screwing, and other fixing means such as an adhesive may be used.

  Examples of the substrate 11 include a metal base substrate obtained by applying an insulating film to a metal base material such as aluminum, a ceramic substrate that is a sintered body of a ceramic material such as alumina, or a resin substrate made of a resin material. Is used. Note that the shape of the substrate 11 is not limited to a circle, and a rectangular substrate may be used.

  A pair of electrode terminals (not shown) is provided on the surface of the substrate 11 as a power feeding unit. A pair of lead wires 71 and 72 led out from the drive circuit 30 are connected to each of the pair of electrode terminals. Further, metal wiring (not shown) for electrically connecting the electrode terminals and the plurality of light emitting elements 12 is formed on the surface of the substrate 11 in a pattern having a predetermined shape.

  A through hole 11 b for inserting a pair of lead wires 71 and 72 led out from the drive circuit 30 is provided at the center of the substrate 11. Note that the through hole 11 b may not be provided in the central portion of the substrate 11. The substrate 11 is not provided with the through hole 11b, but a notch is provided at the edge of the substrate 11 and a pair of lead wires 71 and 72 are inserted into the notch and the pair of electrodes of the substrate 11 is provided. It may be connected to a terminal.

  A plurality of light emitting elements 12 are mounted on one side of the substrate 11. In the present embodiment, the plurality of light emitting elements 12 are arranged on a circumference around the central axis J so as to form an annular array. In FIG. 2, as an example, eight light emitting elements 12 are mounted. However, the number of light emitting elements 12 is not limited to this, and may be one or other than eight. There may be a plurality.

  The light emitting element 12 in the present embodiment is an individually packaged surface mount device (SMD) type LED element. As shown in FIGS. 1 and 2, a container (package) 12a, a container, The LED chip 12b primarily mounted in 12a and the sealing member 12c which seals the LED chip 12b are provided. The light emitting element 12 that is an SMD type LED element is secondarily mounted on the substrate 11.

  The container 12a is a resin molded product made of white resin or a white ceramic molded product, and has an inverted frustoconical concave portion (cavity). The inner surface of the recess is inclined and is configured to reflect light from the LED chip 12b upward.

  The LED chip 12b is mounted on the bottom surface of the recess of the container 12a. The LED chip 12b is an example of a semiconductor light emitting element that emits light with a predetermined direct-current power, and is a bare chip that emits monochromatic visible light. The LED chip 12b is, for example, a blue LED chip that emits blue light when energized.

  The sealing member 12c is a light-transmitting insulating resin material such as silicone resin. The sealing member 12c in the present embodiment includes a phosphor as a wavelength conversion material that converts the wavelength of light from the LED chip 12b. That is, the sealing member 12c is a phosphor-containing resin in which a phosphor is contained in a translucent resin, and wavelength-converts (color converts) light from the LED chip 12b to a predetermined wavelength. The sealing member 12c is filled in the recess of the container 12a.

  As the sealing member 12c, for example, when the LED chip 12b is a blue LED, a phosphor-containing resin obtained by dispersing YAG (yttrium, aluminum, garnet) -based yellow phosphor particles in a silicone resin in order to obtain white light. Can be used. As a result, the yellow phosphor particles are excited by the blue light of the blue LED chip to emit yellow light, so that the sealing member 12c generates white light as a combined light of the excited yellow light and the blue light of the blue LED chip. Light is emitted. The sealing member 12c may contain a light diffusing material such as silica.

  The plurality of light emitting elements 12 configured in this way are connected in series, for example, and emit light by DC power supplied from the drive circuit 30 via a pair of lead wires 71 and 72. Note that the connection mode of the plurality of light emitting elements 12 (series connection, parallel connection, combination connection of series connection and parallel connection, etc.) is not particularly limited.

[Glove]
The globe 20 is a translucent cover that covers the LED module 10 and is configured to take out light emitted from the LED module 10 to the outside of the lamp. That is, the light of the LED module 10 that has entered the inner surface of the globe 20 passes through the globe 20 and is extracted to the outside of the globe 20.

  The globe 20 is a hollow member having an opening 21 and has a substantially spherical shape with the top on the opposite side of the opening 21 closed. As shown in FIG. 1, the globe 20 is a hollow rotating body having a central axis J as a rotation axis, for example, and has a shape in which the opening 21 is narrowed.

  The opening 21 of the globe 20 presses the heat sink 40 toward the base 60, and the end of the opening 21 of the globe 20 contacts the surface of the first heat transfer plate 41 of the heat transfer pieces 40 a to 40 d of the heat sink 40. ing. In this state, the globe 20 is fixed to the opening on the globe side of the housing 50. For example, the opening 21 of the globe 20 and the outer portion 51 of the housing 50 are fixed by an adhesive such as silicone resin.

  As the material of the globe 20, a translucent material made of a glass material such as silica glass transparent to visible light, or a resin material such as acrylic (PMMA) or polycarbonate (PC) can be used.

  The globe 20 is preferably subjected to a diffusion treatment for diffusing light emitted from the LED module 10. For example, the light diffusing function can be given to the globe 20 by forming a light diffusion film (light diffusion layer) on the inner surface or the outer surface of the globe 20.

  Specifically, a milky white light diffusing film can be formed by applying a resin containing a light diffusing material such as silica or calcium carbonate, a white pigment or the like to the entire inner surface or outer surface of the globe 20. Alternatively, the globe 20 can be provided with a light diffusion function by forming a plurality of light diffusion dots or a plurality of minute depressions on the globe 20. As described above, by providing the globe 20 with the light diffusion function, the light incident on the globe 20 from the LED module 10 can be diffused, so that the light distribution angle can be widened.

  In addition, you may make the globe 20 transparent so that the LED module 10 inside can be visually recognized without giving the light diffusion function to the globe 20. In addition, the shape of the globe 20 may be a spheroid or oblate sphere, or may be a shape conforming to an A-type bulb that is a general bulb shape.

[Drive circuit]
The drive circuit 30 is a power supply circuit (power supply unit) for driving the LED module 10, and supplies power to the LED module 10 for causing the LED module 10 (light emitting element 12) to emit light. For example, the drive circuit 30 converts AC power supplied from the base 60 via a pair of lead wires 73 and 74 into DC power, and the DC power is supplied to the LED module 10 via a pair of lead wires 71 and 72. Supply. The LED module 10 (light emitting element 12) is turned on and off by the DC power supplied from the drive circuit 30 (lighting circuit).

  The drive circuit 30 includes a circuit board 31 and a plurality of electronic components 32 mounted on the circuit board 31. The drive circuit 30 is disposed between the LED module 10 and the base 60. Specifically, the drive circuit 30 is housed in an inner shell 52 of the housing 50 and is fixed to the inner shell 52 by screwing, bonding, engagement, or the like.

  The circuit board 31 is a printed circuit board (PCB) in which metal wiring such as copper foil is patterned on one surface (solder surface). The plurality of electronic components 32 mounted on the circuit board 31 are electrically connected to each other by metal wiring formed on the circuit board 31. For example, the circuit board 31 is arranged in a posture (vertically placed) in which the main surface of the circuit board 31 is substantially parallel to the central axis J. The circuit board 31 is not limited to the vertical arrangement, and the main surface of the circuit board 31 may be arranged in a posture (horizontal arrangement) substantially orthogonal to the central axis J.

  The electronic component 32 is a plurality of circuit elements for lighting the LED module 10. For example, a capacitive element such as an electrolytic capacitor or a ceramic capacitor, a resistive element such as a resistor, a rectifier circuit element, a coil element, a choke coil (choke) A semiconductor element such as a transformer), a noise filter, a diode, or an integrated circuit element. Note that an electronic component 32 (circuit component) having low heat resistance such as an electrolytic capacitor may be mounted on the end of the circuit board 31 on the base 60 side.

  The drive circuit 30 configured as described above is ensured by being housed in the inner portion 52 of the casing 50 made of insulating resin. The drive circuit 30 may be combined with a dimmer circuit, a booster circuit, or the like.

  The drive circuit 30 and the LED module 10 are electrically connected by a pair of lead wires 71 and 72. The drive circuit 30 and the base 60 are electrically connected by a pair of lead wires 73 and 74. These four lead wires 71 to 74 are, for example, alloy copper lead wires, and include a core wire made of alloy copper and an insulating resin coating that covers the core wire.

  The pair of lead wires 71 and 72 are electric wires that supply DC power from the drive circuit 30 to the LED module 10. For example, the lead wire 71 is a high voltage side output terminal wire, and the lead wire 72 is a low voltage side output terminal wire. The lead wires 71 and 72 are inserted into through holes provided in the heat sink 40 and through holes provided in the LED module 10 and connected to the substrate 11 of the LED module 10.

  The lead wires 73 and 74 are electric wires for supplying AC power from the base 60 to the drive circuit 30. The lead wire 73 is connected to the shell portion 61 of the base 60. On the other hand, the lead wire 74 is connected to the eyelet portion 63 of the base 60.

[heatsink]
The heat sink 40 is a heat radiating member that mainly radiates heat generated in the LED module 10. The heat sink 40 is composed of a plurality of heat transfer pieces (heat transfer bodies). That is, the heat sink 40 is divided (separated) into a plurality of heat transfer pieces, and is configured by combining these heat transfer pieces. In the present embodiment, the heat sink 40 is composed of four heat transfer pieces 40a to 40d.

  Each of the heat transfer pieces 40 a to 40 d includes a first heat transfer plate 41 and a second heat transfer plate 42. In the present embodiment, each of the four heat transfer pieces 40a to 40d is the same product, and has the same shape and the same size.

  In each heat transfer piece 40a-40d, the 1st heat transfer plate 41 is a fixing | fixed part to which the LED module 10 is fixed, Comprising: In this Embodiment, it is a plate-shaped metal member. The LED module 10 is supported by the first heat transfer plates 41 of the four heat transfer pieces 40a to 40d. Specifically, the substrate 11 of the LED module 10 is placed on one surface of the first heat transfer plate 41 so as to be in contact therewith. Since the first heat transfer plate 41 and the LED module 10 are fixed by screwing with screws 80, the first heat transfer plate 41 is provided with a through hole 41a for inserting the screws 80.

  The other surface of the first heat transfer plate 41 is in contact with the end of the inner wall 52 of the housing 50 on the globe 20 side. Accordingly, each of the four heat transfer pieces 40 a to 40 d is supported by the inner shell 52 of the housing 50. That is, the heat sink 40 is supported by the housing 50 in a state where the LED module 10 is fixed to the heat sink 40.

  As described above, the end of the opening 21 of the globe 20 is in contact with one surface of the first heat transfer plate 41. That is, the first heat transfer plate 41 is sandwiched between the opening 21 of the globe 20 and the inner shell 52 of the housing 50, and is pressed against the inner shell 52 of the housing 50 by the globe 20.

  In each of the heat transfer pieces 40 a to 40 d, the second heat transfer plate 42 is erected from the end of the first heat transfer plate 41 and is formed to be bent from the first heat transfer plate 41. . In the present embodiment, the second heat transfer plate 42 is a plate-shaped metal member.

  Further, the second heat transfer plate 42 faces the inner surface of the outer portion 51 of the housing 50. The second heat transfer plate 42 has a shape along the inner surface shape of the outer shell 51 of the housing 50. Specifically, the surface of the second heat transfer plate 42 is a tapered surface (an inclined surface) configured to be inclined with respect to the central axis J. Further, the second heat transfer plate 42 and the outer portion 51 of the casing 50 are not in contact with each other, and a gap (air layer) exists between the second heat transfer plate 42 and the outer portion 51.

  In the present embodiment, each of the four heat transfer pieces 40a to 40d is a pressed product of a metal plate. For example, each heat-transfer piece 40a-40d can be formed by giving a bending process etc. to metal plates, such as an aluminum plate. More specifically, a heat transfer piece having a plate-like first heat transfer plate 41 and a plate-like second heat transfer plate 42 is formed by bending a metal plate having a constant thickness into a substantially L shape. be able to.

  As shown in FIG. 3, each of the four heat transfer pieces 40 a to 40 d is arranged around the central axis J of the LED bulb 1. FIG. 3 is a top view of the heat sink 40 in the LED bulb 1 according to the embodiment.

  Specifically, the four heat transfer pieces 40a to 40d are evenly arranged at intervals of 90 degrees in the circumferential direction around the central axis J. Further, the four heat transfer pieces 40a to 40d are arranged in the housing 50 so that there is a gap between adjacent heat transfer pieces. Specifically, there is a gap between the heat transfer pieces 40a and 40b, between the heat transfer pieces 40b and 40c, between the heat transfer pieces 40c and 40d, and between the heat transfer pieces 40d and 40a. Is present.

  The four heat transfer pieces 40a to 40d are arranged so that there is a gap between the adjacent heat transfer pieces, but may be arranged so that there is no gap between the adjacent heat transfer pieces.

  Thus, the heat sink 40 is configured by combining the four heat transfer pieces 40a to 40d, and the drive circuit 30 is disposed inside the heat sink 40 as shown in FIG. The heat sink 40 is disposed between the LED module 10 and the base 60. In the present embodiment, the second heat transfer plate 42 of the heat sink 40 is disposed around the inner shell 52 so as to surround the inner shell 52 of the housing 50. That is, the heat sink 40 surrounds the drive circuit 30 via the inner portion 52 of the housing 50.

[Case]
The housing 50 is disposed between the globe 20 and the base 60. The housing 50 includes an outer portion 51 (first housing portion) that surrounds at least a part of the periphery of the heat sink 40. Furthermore, the housing 50 includes an inner shell 52 (second housing portion) as a portion disposed inside the heat sink 40. The base of the outer shell 51 on the base 60 side is connected to the inner shell 52. Specifically, the end portion on the base 60 side of the outer portion 51 is connected to the inner portion 52.

  The outer portion 51 is an exposed portion exposed to the outside (in the atmosphere) of the housing 50 and constitutes an outer member of the LED bulb 1. Therefore, the outer surface of the outer shell 51 is exposed to the outside. Further, the outer portion 51 is configured to surround all the second heat transfer plates 42 of the heat transfer pieces 40 a to 40 d constituting the heat sink 40.

  The outer portion 51 has, for example, a substantially cylindrical shape with a constant thickness and an inner diameter and an outer diameter that gradually change. The inner peripheral surface and outer peripheral surface of the outer shell 51 are tapered surfaces (inclined surfaces) configured to be inclined with respect to the central axis J. In the present embodiment, the outer shell 51 is configured such that the inner diameter and the outer diameter gradually decrease toward the base 60 side.

  Further, the outer shell 51 and the second heat transfer plate 42 are disposed to face each other, and the inner surface of the outer shell 51 and the outer surface of the second heat transfer plate 42 face each other. The inner surface shape of the outer shell 51 is a shape along the surface shape of the second heat transfer plate 42.

  A clearance is set between the outer shell 51 and the second heat transfer plate 42, and a gap (space) exists. That is, the outer shell 51 and the second heat transfer plate 42 are configured not to contact each other. Specifically, the gap between the outer shell 51 and the second heat transfer plate 42 is substantially constant.

  On the other hand, the inner portion 52 is a cylindrical body configured to surround the drive circuit 30. That is, the inner portion 52 functions as a circuit case that protects the drive circuit 30. The inner portion 52 is, for example, a substantially cylindrical shape having a constant thickness and a constant inner diameter and outer diameter.

  In the present embodiment, the inner portion 52 has a cylindrical shape formed so as to extend in the direction of the central axis J of the LED bulb 1. The inner shell 52 is configured to sandwich the second heat transfer plate 42 of the heat sink 40 with the outer shell 51. That is, the housing 50 has a double structure of the outer portion 51 and the inner portion 52 with the second heat transfer plate 42 interposed therebetween.

  There is a gap (space) between the inner shell 52 and the second heat transfer plate 42. That is, the inner shell 52 and the second heat transfer plate 42 are configured not to contact each other. A gap between the inner shell 52 and the second heat transfer plate 42 is large on the globe 20 side and gradually narrows toward the base 60 side. In addition, the gap between the inner shell 52 and the second heat transfer plate 42 is larger than the gap between the outer shell 51 and the second heat transfer plate 42.

  A threaded portion 52a is formed in a portion of the inner portion 52 that extends toward the base 60 side. The screwing part 52 a is screwed with the base 60. That is, the base 60 is screwed into the screwing portion 52a.

  The inner portion 52 is provided with a structure for fixing the circuit board 31 of the drive circuit 30. That is, the inner portion 52 also functions as a holding portion (holder) that holds the drive circuit 30.

  The housing 50 configured in this manner is integrally formed of resin. That is, the outer part 51 and the inner part 52 are formed by integral molding. The housing 50 can be made of an insulating resin material such as polybutylene terephthalate (PBT).

[Base]
The base 60 is a power receiving unit that receives power for causing the LED module 10 (light emitting element 12) to emit light from the outside of the lamp. The base 60 is attached to a socket of a lighting fixture, for example. Thereby, the base 60 can receive electric power from the socket of the lighting fixture when the LED bulb 1 is turned on.

  AC power is supplied to the base 60 from, for example, a commercial power source. The base 60 in the present embodiment receives AC power through two contact points, and the power received by the base 60 is input to the drive circuit 30 via a pair of lead wires 73 and 74.

  The base 60 has a bottomed cylindrical shape made of metal and includes a shell portion 61 whose outer peripheral surface is a male screw, and an eyelet portion 63 attached to the shell portion 61 via an insulating portion 62. The insulating part 62 is made of glass cullet, for example.

  On the outer peripheral surface of the base 60, a screwing portion for screwing into the socket of the lighting fixture is formed. Further, on the inner peripheral surface of the base 60, a screwing portion for screwing with the screwing portion 52 a of the inner shell portion 52 of the housing 50 is formed. The base 60 is externally fitted to the housing 50 (inner part 52) by being screwed into the screwed part 52 a of the inner part 52.

  The type of the base 60 is not particularly limited, but in the present embodiment, a screwed-type Edison type (E type) base is used. For example, E26 type, E17 type, E16 type, etc. are mentioned as the nozzle | cap | die 60. Further, as the base 60, a plug-in base may be used.

[Assembly method of LED bulb]
Next, an example of an assembly method of the LED bulb 1 will be described with reference to FIG. FIG. 4 is a view for explaining a state when the heat sink 40 is assembled into the housing 50.

  First, as shown in FIG. 4, the four heat transfer pieces 40 a to 40 d are assembled in the housing 50. Specifically, the second heat transfer plate 42 of each heat transfer piece 40a to 40d is moved to the housing until the first heat transfer plate 41 of each heat transfer piece 40a to 40d comes into contact with the inner shell 52 of the housing 50. It is inserted into the gap between the outer shell 51 and the inner shell 52 of the body 50. At this time, the drive circuit 30 may be disposed in the housing 50 in advance, or may be disposed in the housing 20 after the heat transfer pieces 40 a to 40 d are assembled in the housing 50.

  Next, the LED module 10 is fixed to the four heat transfer pieces 40a to 40d. Specifically, the LED module 10 (substrate 11) is placed on the first heat transfer plate 41 of each of the heat transfer pieces 40a to 40d, and the through hole 11a of the substrate 11 and the through hole 41a of the first heat transfer plate 41 are placed. Are fixed with screws 80.

  Thereafter, the lead wires 71 and 72 led out from the drive circuit 30 are connected to the LED module 10 to fix the globe 20 to the housing 50. Further, the lead wires 73 and 74 led out from the drive circuit 30 are connected to the base 60, and the base 60 is screwed into the threaded portion 52 a of the inner portion 52 of the housing 50. Thereby, the LED bulb 1 is completed.

[Function and effect]
Next, the operation and effect of the LED bulb 1 in the present embodiment will be described including the background of obtaining one mode of the LED bulb 1 in the present embodiment.

  Generally, in an LED light bulb, a heat radiating member is used to dissipate heat generated in the LED module.

  For example, a disk-shaped metal plate on which the LED module is placed and a cylindrical heat sink that fits the metal plate and surrounds the drive circuit are provided as the heat radiating member. For this reason, it is necessary to manufacture the metal plate and the heat sink separately, and the number of parts of the heat dissipating component increases, and the manufacturing cost (processing cost, material cost, etc.) of the entire heat dissipating component increases.

  Further, the heat sink is formed, for example, in a cylindrical shape so as to surround the drive circuit using a high heat conductive material such as metal.

  In this case, if the heat sink is used as the outer casing, the shape of the heat sink becomes complicated, and the manufacturing cost of the heat sink becomes very high. In this case, the heat sink can be manufactured by, for example, aluminum die casting, but the processing cost of the heat sink becomes high.

  On the other hand, when the outer casing surrounding the heat sink is separately provided without using the heat sink as the outer casing, the heat sink is formed in a cylindrical shape along the tapered inner shape of the outer casing, for example. In this case, the heat sink can be manufactured, for example, by drawing, but in this case as well, the heat sink processing cost increases.

  On the other hand, in the LED bulb 1 according to the present embodiment, the heat sink 40 is configured by a plurality of heat transfer pieces 40a to 40d, and the heat sink 40 is divided. Further, the heat transfer pieces 40 a to 40 d constituting the heat sink 40 include a first heat transfer plate 41 and a second heat transfer plate 42 formed so as to be bent from the first heat transfer plate 41.

  Thereby, the heat sink 40 can be formed by press working. That is, one heat sink 40 can be obtained by forming each of the plurality of heat transfer pieces 40a to 40d by press working such as bending and combining the plurality of heat transfer pieces 40a to 40d. Thus, since the processing cost of the heat sink 40 can be suppressed by forming the plurality of heat transfer pieces 40a to 40d by press processing, the heat sink 40 can be manufactured at low cost.

  Moreover, by dividing the heat sink 40 into a plurality of parts (heat transfer pieces 40a to 40d) rather than forming a single cylindrical part, the processing accuracy (dimensional accuracy) of the parts can be moderated. In this sense, the heat sink 40 can be manufactured at a low cost.

  Further, in each of the plurality of heat transfer pieces 40 a to 40 d constituting the heat sink 40, the LED module 10 is fixed to the first heat transfer plate 41, and the second heat transfer plate 42 is formed on the outer portion 51 of the casing 50. Facing the inner surface.

  Thereby, since the LED module 10 can be directly fixed to the heat sink 40, it is not necessary to use a separate metal plate only for mounting the LED module 10. In addition, the heat generated in the LED module 10 is directly conducted to the first heat transfer plate 41 of each of the heat transfer pieces 40a to 40d, and is conducted through the second heat transfer plate 42 from the outer portion 51 of the housing 50 to the LED bulb. 1 radiates heat to the outside. Therefore, the heat generated in the LED module 10 can be efficiently radiated to the outside of the LED bulb 1.

  As described above, according to the LED bulb 1 in the present embodiment, the heat generated in the LED module 10 can be efficiently radiated by the low-cost heat sink 40. In the present embodiment, each of the heat transfer pieces 40a to 40d constituting the heat sink 40 is a pressed product of a metal plate.

  Furthermore, according to the LED bulb 1 in the present embodiment, the following operational effects can also be achieved.

  In a conventional LED bulb, when a cylindrical outer casing is separately provided so as to surround the cylindrical heat sink, the linear expansion coefficient between the heat sink and the outer casing is determined by placing the outer casing and the heat sink in contact with or in proximity to each other. There is a problem in that the outer casing and the heat sink deteriorate due to stress due to a difference in thermal expansion or shrinkage due to the difference.

  For example, if a resin outer casing is provided so as to surround a metal heat sink so as to be in contact with each other, the heat sink and outer casing are thermally expanded (volume expansion) by the heat from the drive circuit and the LED module when the LED bulb is turned on. However, since the resin casing has a linear expansion coefficient (thermal expansion coefficient) several times higher than that of the metal heat sink, the heat sink expands more thermally than the outer casing. Due to this difference in thermal expansion, stress distortion may occur in the resin outer casing and cracks may occur. Conversely, when the LED bulb 1 is cooled, a crack or the like may occur in the outer casing due to a difference in heat shrinkage between the heat sink and the outer casing.

  In contrast, in the LED bulb 1 according to the present embodiment, as described above, the heat sink 40 is configured by the plurality of heat transfer pieces 40a to 40d, and the heat sink 40 is divided.

  Thereby, stress is applied from one of the heat sink 40 and the casing 50 to the other due to the difference in thermal expansion and thermal contraction due to the difference in linear expansion coefficient between the heat sink 40 (second heat transfer plate 42) and the casing 50 (outer portion 51). Giving and receiving can be suppressed. Therefore, the effect that it can suppress that the heat sink 40 and the housing | casing 50 deteriorate is also acquired. In particular, the occurrence of cracks or the like in the resin casing 50 can be suppressed.

  Further, by combining the plurality of heat transfer pieces 40a to 40d into one heat sink 40, the heat transfer pieces 40a to 40a suitable for the required heat dissipation characteristics or size of the heat sink 40 according to the type of the LED bulb 1 are used. The number of 40d can be appropriately adjusted. That is, the effect that the desired heat sink 40 can be obtained is also acquired by adjusting the combination number of the heat-transfer pieces 40a-40d. For example, in the case of a large LED bulb, the number of heat transfer pieces 40a to 40d to be combined may be increased. In this case, the number of parts can be reduced by making each of the heat transfer pieces 40a to 40d the same product.

  Further, as described above, the LED module 10 is fixed to the heat sink 40 by dividing the heat sink 40 into a plurality of heat transfer pieces 40a to 40d and making each of the heat transfer pieces 40a to 40d into a pressed product of a metal plate. The through-hole 41a for carrying out can also be obtained cheaply and easily. That is, in order to fix the LED module 10, it is difficult to form a part where metal is bent at the opening of the cylindrical heat sink and form a through hole in the bent part. Processing costs are very high. On the other hand, by setting the heat sink 40 to the above configuration, the heat transfer pieces 40a to 40d can be manufactured by performing press working after forming the through holes 41a in the heat transfer plate such as a metal plate. Thereby, the heat-transfer pieces 40a-40d which have the 1st heat-transfer plate 41 which has the through-hole 41a, and the 2nd heat-transfer plate 42 can be produced cheaply and easily.

  Furthermore, by dividing the heat sink 40 into a plurality of heat transfer pieces 40a to 40d, an effect that the heat sink 40 can be easily incorporated into the housing 50 is also obtained. In other words, if the heat sink has a tapered cylindrical shape, the tapered opening of the heat sink cannot be inserted into the gap between the outer portion 51 and the inner portion 52 of the housing 50, but the heat sink as in the present embodiment. Even if the heat sink 40 is tapered as a whole, the heat sink 40 is divided (separated) into a plurality of heat transfer pieces 40a to 40d, so that each heat transfer piece 40a to 40d is placed between the outer portion 51 and the inner portion 52. It can be easily inserted into the gap.

  Further, like the LED bulb 1 in the present embodiment, each of the heat transfer pieces 40 a to 40 d may be arranged around the central axis J of the LED bulb 1.

  Thereby, since each heat-transfer piece 40a-40d can be produced in the same shape, a heat sink can be produced at low cost.

  Moreover, in the LED bulb 1 in the present embodiment, as shown in FIG. 3, in the heat transfer pieces 40 a to 40 d arranged around the central axis J, there is a gap between adjacent heat transfer pieces. Existing.

  As a result, even if the heat sink 40 (second heat transfer plate 42) and the casing 50 (outer portion 51) are thermally expanded or contracted, there is a difference in thermal expansion or thermal contraction between the heat sink 40 and the casing 50. Stress can be absorbed by the gap between adjacent heat transfer pieces. Thereby, it can further suppress that heat sink 40 and case 50 deteriorate.

  In addition, like the LED bulb 1 in the present embodiment, the second heat transfer plate 42 in each of the heat transfer pieces 40 a to 40 d may have a shape along the inner surface shape of the outer portion 51 of the housing 50.

  Thereby, the heat of the LED module 10 conducted to the second heat transfer plate 42 can be efficiently radiated to the outside through the outer portion 51 of the housing 50. Therefore, the heat dissipation of the LED bulb 1 is further improved.

  In this case, by providing a gap between the second heat transfer plate 42 and the outer portion 51, the stress associated with the difference in thermal expansion or contraction between the heat sink 40 and the housing 50 is applied to the second heat transfer plate. It can absorb in the clearance gap between 42 and the outer part 51. FIG. Thereby, deterioration of the heat sink 40 and the housing | casing 50 can be suppressed further.

  Further, like the LED bulb 1 in the present embodiment, the housing 50 may have an inner portion 52 that surrounds the drive circuit 30.

  As a result, the inner portion 52 can function as a circuit case of the drive circuit 30, and thus the insulation of the drive circuit 30 can be ensured by the inner portion 52.

  In this case, by providing a gap between the second heat transfer plate 42 and the inner shell 52, the stress associated with the difference in thermal expansion or contraction between the heat sink 40 and the housing 50 can be applied to the second heat transfer plate. Even a gap between the plate 42 and the inner shell 52 can be absorbed. Thereby, deterioration of the heat sink 40 and the housing | casing 50 can be suppressed further.

  Moreover, the base on the base side of the outer portion 51 may be connected to the inner portion 52 as in the LED bulb 1 in the present embodiment.

  Thereby, since the outer part 51 and the inner part 52 can be produced by integral molding, the number of parts can be reduced and the cost can be reduced. Specifically, a component that functions as a circuit case of the drive circuit 30 and a component that functions as an outer casing can be manufactured by integral molding. Therefore, it is not necessary to separately manufacture the circuit case and the outer casing, so that the mold cost can be reduced, and the casing 50 can be manufactured at a low cost.

  Moreover, the housing | casing 50 is good to be integrally shape | molded with resin like the LED bulb 1 in this Embodiment.

  Thereby, the outer part 51 functioning as a circuit case and the inner part 52 functioning as an outer casing can be integrally formed by resin molding. That is, the housing 50 can be an integrally molded product made of resin. Thereby, the housing | casing 50 can be produced easily at low cost.

[Lighting device]
FIG. 5 is a schematic cross-sectional view of the illumination device 2 according to the embodiment.

  As shown in FIG. 5, the illuminating device 2 which concerns on this Embodiment is attached and used for the indoor ceiling etc., for example. The lighting device 2 includes the LED bulb 1 according to the above embodiment and a lighting fixture 3.

  The lighting fixture 3 turns off and turns on the LED bulb 1 and includes a fixture body 4 attached to the ceiling and a lamp cover 5 that covers the LED bulb 1.

  The appliance main body 4 has a socket 4 a for attaching the base 60 of the LED bulb 1 and supplying power to the LED bulb 1. A base 60 of the LED bulb 1 is screwed into the socket 4a, and electric power is supplied to the LED bulb 1 through the socket 4a. A translucent plate may be provided in the opening of the lamp cover 5.

(Modification 1)
FIG. 6 is a cross-sectional view of the LED bulb 1A according to the first modification.

  In the LED bulb 1 in the embodiment shown in FIG. 1, the inner portion 52 of the housing 50 extends in the direction of the central axis J of the LED bulb 1. The inner portion 52A of the body 50A is a tapered surface (inclined surface) configured to be inclined with respect to the central axis J of the LED bulb 1A.

  Specifically, in the present modification, the shape of the inner portion 52 facing the second heat transfer plate 42 is a shape along the surface shape of the second heat transfer plate 42. Further, the gap between the inner portion 52 and the outer portion 51 is also constant. For this reason, the gap between the inner shell 52 and the second heat transfer plate 42 is substantially constant.

  As described above, the LED bulb 1 </ b> A according to the present modification can achieve the same effects as those of the LED bulb 1 in the above embodiment, such as being able to efficiently dissipate heat generated by the LED module 10 with the low-cost heat sink 40.

  Furthermore, in the LED bulb 1A in this modification, the inner portion 52A of the housing 50A is inclined with respect to the central axis J of the LED bulb 1A. Thereby, since the storage space of the drive circuit 30 can be increased as compared with the LED bulb 1 in the above embodiment, the degree of freedom in designing the drive circuit 30 can be increased.

(Modification 2)
FIG. 7 is a partial cross-sectional view of an LED bulb 1B according to Modification 2.

  In the LED bulb 1 according to the embodiment shown in FIG. 1, the first heat transfer plate 41 of the heat sink 40 is located closer to the base 60 than the opening end of the outer portion 51 of the housing 50. In the LED bulb 1 </ b> B in the example, the first heat transfer plate 41 of the heat sink 40 is located closer to the globe 20 than the opening end of the outer portion 51 of the housing 50.

  Specifically, in this modification, the second heat transfer plate 42 is extended to the globe 20 side, and the first heat transfer plate 41 of the heat sink 40 is from the end of the opening of the outer portion 51 of the housing 50B. Is also located so as to protrude to the globe 20 side.

  Thereby, in this modification, compared with the said embodiment, the LED module 10 mounted in the 1st heat exchanger plate 41 of the heat sink 40 is located in the inside of the globe 20. FIG.

  In the present modification, the opening of the globe 20 is installed at the step provided at the end of the opening 21 of the outer portion 51 of the casing 50, but the present invention is not limited to this. For example, a recess may be provided at the end of the opening of the outer shell 51 of the housing 50, and the opening 21 of the globe 20 may be fitted into the recess.

  As described above, the LED bulb 1B in the present modification can also obtain the same effects as those of the LED bulb 1 in the above embodiment, such as being able to efficiently dissipate the heat generated in the LED module 10 by the low-cost heat sink 40.

(Other variations)
As described above, the illumination light source and the illumination device according to the present invention have been described based on the embodiment and the modification. However, the present invention is not limited to the above-described embodiment and modification.

  For example, in the above-described embodiment and modification, the heat sink 40 is divided into four parts and is composed of the four heat transfer pieces 40a to 40b, but is not limited thereto. As an example, as shown in FIG. 8, the heat sink 40A may be configured by three heat transfer pieces 40aA, 40bA, and 40cA.

  Moreover, in said embodiment and modification, although the LED module 10 was comprised by the board | substrate 11 of 1 sheet, it is not restricted to this. For example, as shown in FIG. 9, an LED module 10 </ b> A configured using a substrate 11 </ b> A divided into four so as to correspond to the four heat transfer pieces 40 a to 40 d may be used. With this configuration, after the LED module 10A is fixed (screwed) to the four heat transfer pieces 40a to 40d, the heat transfer pieces 40a to 40d can be incorporated into the housing 50. The plurality of divided substrates 11A may be electrically connected separately by lead wires or the like, or the light emitting elements 12 of each substrate 11A may be introduced by introducing eight lead wires from the drive circuit 30. You may comprise so that it can drive independently. In addition, the number of heat transfer pieces and the number of divisions of the substrate do not necessarily need to match.

  Moreover, in said embodiment and modification, although each of the several heat-transfer piece which comprises the heat sink 40 was made into the same product, it is not restricted to this. Each of the plurality of heat transfer pieces constituting the heat sink 40 may be a part having a different shape, or a part of a part having a different shape may be included. However, the cost can be reduced most by making each of the plurality of heat transfer pieces constituting the heat sink 40 the same product.

  In the above-described embodiment, the heat sink 40 is fixed by being sandwiched between the globe 20 (opening 21) and the housing 50 (inner wall 52), but is not limited thereto. For example, the heat sink 40 may be fixed by a locking portion (such as a claw) provided in the housing 50 or may be fixed by screwing a part of the housing 50.

  Moreover, in said embodiment and modification, although the light emitting element 12 was mentioned as the SMD type LED element, it is not restricted to this. For example, a COB (Chip On Board) type LED module in which a bare chip is directly mounted (primary mounting) on a substrate may be used. That is, the LED chip itself may be employed as the light emitting element 12. In this case, the plurality of LED chips may be collectively or individually sealed with a sealing member. The sealing member may contain a wavelength conversion material such as a yellow phosphor as described above.

  In the above-described embodiment and modification, the light-emitting element 12 is a BY type white LED element that emits white light using a blue LED chip and a yellow phosphor, but is not limited thereto. For example, a phosphor-containing resin containing a red phosphor and a green phosphor may be used and combined with this and a blue LED chip to emit white light. In addition to the yellow phosphor, a red phosphor or a green phosphor may be further mixed for the purpose of improving color rendering. Moreover, you may use the LED chip which light-emits colors other than blue, for example, using the ultraviolet LED chip which emits the ultraviolet light which is shorter wavelength than the blue light which a blue LED chip emits, mainly by ultraviolet light You may comprise so that white light may be emitted by the blue fluorescent substance, green fluorescent substance, and red fluorescent substance which are excited and discharge | release blue light, red light, and green light.

  Further, in the above embodiments and modifications, the LED is exemplified as the light emitting element. However, a semiconductor light emitting element such as a semiconductor laser, a light emitting element such as an organic EL (Electro Luminescence) or an inorganic EL, and other solid light emitting elements are used. May be.

  In addition, the form obtained by making various modifications conceived by those skilled in the art to the above-described embodiments and modifications, or the components and functions in the above-described embodiments and modifications without departing from the spirit of the present invention. Forms realized by arbitrarily combining these are also included in the present invention.

1, 1A, 1B LED bulb (light source for illumination)
2 Lighting device 10, 10A LED module (light emitting module)
20 Globe 30 Drive circuit 40, 40A Heat sink 40a, 40b, 40c, 40d, 40aA, 40bA, 40cA Heat transfer piece 41 First heat transfer plate 42 Second heat transfer plate 50, 50A Housing 51 Outer part 52, 52A Inner part Part 60 cap 80 screw

Claims (14)

A light emitting module;
A glove covering the light emitting module;
A driving circuit for causing the light emitting module to emit light;
A heat sink surrounding the drive circuit;
A housing having an outer portion surrounding at least a part of the heat sink;
The heat sink is divided into a plurality of heat transfer pieces,
Each of the plurality of heat transfer pieces is formed so as to be bent from the first heat transfer plate to which the light emitting module is fixed, and to be opposed to the inner surface of the outer portion. have a and the heat transfer plate,
The light emitting module is an illumination light source including a substrate placed on the first heat transfer plate and a light emitting element disposed on the substrate . The illumination light source according to claim 1, wherein each of the plurality of heat transfer pieces is a press-formed product of a metal plate. 3. The illumination light source according to claim 1, wherein each of the plurality of heat transfer pieces is arranged around a central axis of the illumination light source. The illumination light source according to claim 3, wherein a gap exists between the adjacent heat transfer pieces. The illumination light source according to any one of claims 1 to 4, wherein the second heat transfer plate has a shape along an inner surface shape of the outer portion. A light emitting module;
A glove covering the light emitting module;
A driving circuit for causing the light emitting module to emit light;
A heat sink surrounding the drive circuit;
A housing having an outer portion surrounding at least a part of the heat sink;
The heat sink is divided into a plurality of heat transfer pieces,
Each of the plurality of heat transfer pieces is formed so as to be bent from the first heat transfer plate to which the light emitting module is fixed, and to be opposed to the inner surface of the outer portion. A heat transfer plate,
The casing further includes an inner portion that sandwiches the second heat transfer plate with the outer portion.
Lighting for the light source. The illumination light source according to claim 6, wherein the inner wall portion extends in a direction of a central axis of the illumination light source. The light source for illumination according to claim 6, wherein a shape of the inner portion facing the second heat transfer plate is along a surface shape of the second heat transfer plate. The illumination light source according to claim 6, wherein the inner portion surrounds the drive circuit. The illumination light source according to any one of claims 6 to 9, wherein a base on the base side of the outer portion is connected to the inner portion. The illumination light source according to any one of claims 1 to 10, wherein the casing is integrally formed of resin. The light source for illumination according to any one of claims 6 to 10 , wherein the light emitting module includes a substrate placed on the first heat transfer plate and a light emitting element disposed on the substrate. The illumination light source according to any one of claims 1 to 5, wherein the substrate and the first heat transfer plate are screwed together. An illumination device comprising the illumination light source according to any one of claims 1 to 13 .

Images